Various types of monitoring and alarm systems are known. In many of these systems, modules such as fire, smoke or gas detectors are coupled via a wired medium, cables, for example, to a control unit or fire alarm panel. Such systems always reflect installation, operational and maintenance costs associated with the wired medium.
Examples of monitoring and fire detection systems are found in U.S. Pat. No. 5,483,222 to Tice entitled “Multiple Sensor Apparatus and Method” and U.S. Pat. No. 6,163,263 to Tice et al. entitled “Circuitry for Electrical Device in Multi-Device Communications System”, which are assigned to the assignee hereof.
There is an ongoing need to reduce the costs of installing and maintaining such systems. There is also an ongoing need to be able to conveniently and cost effectively modify the configuration of such systems, due to remodeling for example, or expansion of a monitored region.
In response to these needs, labor costs and time involved in installation have been reduced by developing wireless fire systems based on a network of battery operated devices. These wireless fire systems are based on low data rate protocols that suffer from bandwidth limitations resulting in reduced capacity and increased detection and activation latency. These wireless fire systems cannot support additional communication needed to support voice evacuation on the same network. Using a standard wireless protocol radio can help in reducing the cost of the wireless fire devices. However, most of the standard based protocols use CSMA/CA channel access protocol which cannot offer deterministic performances in a high capacity, high data generating network. These protocols are not efficient for battery powered devices.